Methane gas sensor

An apparatus and method for detection of methane in an environment, including a housing with a sensor printed circuit board and a processor printed circuit board interconnected to and thermally insulated from the sensor printed circuit board. The sensor printed circuit board includes a first tuning fork isolated from the environment, and a second tuning fork exposed to the environment. The tuning forks are attached to opposite sides of the sensor printed circuit board. The processor printed circuit board includes processing circuitry interconnected to the first tuning fork and the second tuning fork, which receives vibration frequency signals therefrom, and is programmed to determine a frequency difference between the frequency of vibration of the first tuning fork and the frequency vibration of the second tuning fork, and if the frequency difference is greater than a predetermined threshold, then setting an alarm to indicate the presence of methane.